1. Field of the Invention
The present invention relates to a camera viewfinder that superimposes an image of an object being photographed with a field of vision frame so as to display boundaries used during photography relative to the image.
2. Description of Related Art
Bright frame viewfinders are known that bring in external light from a light collection window located on an outer surface of the camera and brightly illuminate a field of vision frame, indicating the photographic boundaries of the object being photographed. Since the external light taken in through the light collection window by these bright frame viewfinders at night or in dark places is reduced, the field of vision frame becomes difficult to see.
Therefore, in convention camera viewfinders, an external light source is attached near the light collection window. Such camera viewfinders use these external light sources to illuminate the field of vision frame.
However, with the conventional type of viewfinder, when the object being photographed is in bright conditions, such as in bright daylight conditions, the field of vision frame of the viewfinder can become too bright and disappear completely. Accordingly, sometimes while it is difficult to view the field of vision frame, the composition of the object being photographed cannot be set properly due to the intense light.
In addition, since the indicated field of vision frame (frame) is difficult to distinguish when it is complex, only a comparatively simple field of vision frame may be displayed.
It is conceivable that liquid crystal elements (i.e., a liquid crystal display (LCD)) could be used to display a complex field of vision frame in order to resolve the latter problem. However, since the permeability of liquid crystal elements is low, the field of vision frame can become hard to see.
For additional background information, see U.S. Pat. No. 5,170,204, the disclosure of which is incorporated herein by reference. U.S. Pat. No. 5,170,204 discloses a camera in which a first LCD, through which the photographic image passes, is used to superimpose one or more frames on the photographic image, while a second LCD is used in combination with a light source to project a display of photographic data to a border portion of the photographic image in the viewfinder.